This invention relates to a device for applying powder to a paper web, particularly in a cigarette making machine.
It is known to produce cigarettes in which the cigarette paper wrapper carries a printed legend (or motif), e.g. indicating the name of the brand or manufacturer. Such legends are sometimes required to have a metallic, coloured appearance, commonly simulating gold. Usually bronze powder is used: reference is made hereinafter to "bronze powder" without, however, limiting the type, including colour, of powder to which the invention is applicable.
Known devices for producing legends from bronze powder are usually mounted on the cigarette making machine, upstream of the position at which the cigarette paper is wrapped around the tobacco rod, and include a first section for applying an adhesive imprint to the paper and a second section for applying bronze powder to the paper so that it adheres to the adhesive imprint. Such known devices, which normally include mechanical means such as a roller for applying the powder to the paper and means such as brushes for removing excess applied powder, cannot operate at the speeds of the latest cigarette making machines (which can achieve production rates of 10,000 cigarettes/minute or more).